Leetcode - Valid Sudoku
https://leetcode.com/problems/valid-sudoku/
Determine if a 9x9 Sudoku board is valid. Only the filled cells need to be validated according to the following rules:
-
Each row must contain the digits
1-9
without repetition. -
Each column must contain the digits
1-9
without repetition. -
Each of the 9
3x3
sub-boxes of the grid must contain the digits1-9
without repetition.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 | func isValidSudoku(board [][]byte) bool { hash := map[byte] bool {} for i := 0; i < 9; i++ { hash = map[byte] bool {} for j := 0; j < 9; j++ { if board[i][j] != '.' { if hash[board[i][j]] { return false } hash[board[i][j]] = true } } } for j := 0; j < 9; j++ { hash = map[byte] bool {} for i := 0; i < 9; i++ { if board[i][j] != '.' { if hash[board[i][j]] { return false } hash[board[i][j]] = true } } } for i := 0; i < 9; i += 3{ for j := 0; j < 9; j += 3 { if !checkBox(board, i, j) { return false } } } return true } func checkBox(board [][]byte, m, n int ) bool { hash := map[byte] bool {} for i := m; i < m + 3; i++ { for j := n; j < n + 3; j++ { if board[i][j] != '.' { if hash[board[i][j]] { return false } hash[board[i][j]] = true } } } return true } |